notifications: en overscan, desplaca la Y a la primera fila visible del canvas segons aspect ratio finestra/canvas

source/core/rendering/screen.cpp

@@ -508,14 +508,16 @@ void Screen::clearNotification() {
     notification_message_.clear();
 }
 
-// Dibuja la notificación activa (si la hay) sobre el gameCanvas
+// Dibuja la notificación activa (si la hay) sobre el gameCanvas. La Y es
+// el `notification_y_` configurat, desplacat cap avall si en overscan part
+// de la franja superior queda fora de pantalla.
 void Screen::renderNotification() {
     if (notification_text_ == nullptr || SDL_GetTicks() >= notification_end_time_) {
         return;
     }
     notification_text_->writeDX(Text::FLAG_CENTER | Text::FLAG_COLOR | Text::FLAG_STROKE,
         game_canvas_width_ / 2,
-        notification_y_,
+        notification_y_ + safeNotificationY(),
         notification_message_,
         1,
         notification_text_color_,
@@ -523,6 +525,21 @@ void Screen::renderNotification() {
         notification_outline_color_);
 }
 
+// Y minima del canvas visible. Solo no zero quan estem en overscan i l'aspect
+// de finestra obliga a escalar mes ample que alt (el canvas vertical desborda
+// i la franja superior es retalla). En cas contrari (qualsevol altre mode, o
+// overscan amb retall horitzontal nomes), retorna 0.
+auto Screen::safeNotificationY() const -> int {
+    if (Options::video.presentation_mode != Options::PresentationMode::OVERSCAN) { return 0; }
+    if (window_width_ <= 0 || window_height_ <= 0 || game_canvas_height_ <= 0) { return 0; }
+    const float CANVAS_RATIO = static_cast<float>(game_canvas_width_) / static_cast<float>(game_canvas_height_);
+    const float WINDOW_RATIO = static_cast<float>(window_width_) / static_cast<float>(window_height_);
+    if (WINDOW_RATIO < CANVAS_RATIO) { return 0; }  // retall horitzontal nomes
+    const float OVERSCAN_SCALE = static_cast<float>(window_width_) / static_cast<float>(game_canvas_width_);
+    const float VH = static_cast<float>(game_canvas_height_) * OVERSCAN_SCALE;
+    return static_cast<int>(std::ceil((VH - static_cast<float>(window_height_)) / (2.0F * OVERSCAN_SCALE)));
+}
+
 // ============================================================================
 // Emscripten — fix per a fullscreen/resize (veure el bloc de comentaris al
 // principi del fitxer i l'anonymous namespace amb els callbacks natius).